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1.
ACS Biomater Sci Eng ; 10(3): 1765-1773, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38357873

RESUMEN

While titanium dental implants have already been clinically established, ongoing research is continuously being conducted to advance the fields of osseointegration and bacterial resistance, seeking further improvements in these areas. In this study, we introduce an innovative method for treating titanium surfaces within tightly sealed packaging. Specifically, titanium discs, enclosed in surgical-grade packaging, underwent treatment using cold atmospheric plasma (CAP). The surfaces were thoroughly characterized in terms of wettability, crystalline structure, and chemical composition. Hemocompatibility analyses were conducted using blood diluted in sodium citrate (1:9) exposed to titanium discs for 30 min inside a CO2 incubator at 37 °C. Subsequently, various blood parameters were evaluated, including prothrombin time (PT), activated partial thromboplastin time (APTT), and platelet adhesion. Microbiological analyses were also performed using Pseudomonas aeruginosa (ATCC 27853) for 4 h at 37 °C. The treatment with CAP Jet resulted in a reduction in contact angle without causing any changes in the crystalline structure. No statistically significant differences were observed in the blood parameters. The plasma-treated samples exhibited lower PT and APTT values compared to those of the control group. The surfaces treated with CAP Jet showed increased platelet activation, platelet density, and thrombus formation when compared with the untreated samples. Moreover, the treated surfaces demonstrated lower bacterial colony formation compared with other surfaces.


Asunto(s)
Gases em Plasma , Titanio , Propiedades de Superficie , Titanio/farmacología , Titanio/química , Gases em Plasma/farmacología , Gases em Plasma/química , Humectabilidad , Plaquetas
2.
Microsc Microanal ; 30(1): 169-177, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38252589

RESUMEN

This study aimed to investigate sexual dimorphism in stillborn hawksbill sea turtles (Eretmochelys imbricata) through gonadal morphological characterizations. Macroscopic, light microscopy, and transmission electron analyses were performed for 30 gonad-mesonephros complexes. Female gonads were spindle-shaped and present a translucent whitish appearance with a grainy texture. Male gonads were approximately ovoid with a smooth opaque white surface. A primary sexual difference concerns different marrow structures, with females presenting organized cellularity featuring oocytes, lacunae, and blood vessels, while males presented a distinct organizational medulla pattern marked by testicular cords extending throughout the gonad length. Ultrastructurally, female's stroma presented interstitial cells and an abundant cytoplasm rich in electrodense droplets and large oval germline cells, with a conspicuous and noncentral nucleus. Males, on the other hand, presented testicular cord cells containing small amounts of heterochromatin and approximately triangular apical and basal cytoplasms with an evident nucleolus characteristic of support cells. Additionally, there were cells with a large spherical nucleus compared with the cell size and a relatively scarce cytoplasm, identified as gonocytes. These findings indicate that macroscopic, microscopic, and ultrastructural evaluations are effective and reliable techniques for the sexual identification of stillborn E. imbricata hatchlings.


Asunto(s)
Tortugas , Animales , Masculino , Femenino , Gónadas , Ovario , Oocitos , Folículo Ovárico
3.
J Vet Sci ; 24(5): e49, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38031643

RESUMEN

BACKGROUND: Hystricomorpha rodents display a similar placentation model to humans. The present study was carried out considering the scarcity of information concerning the placental development in agouti. OBJECTIVE: Describe the microscopy of the placenta, subplacenta and yolk sac of agoutis in early pregnancy and report on the inversion of the yolk sac. METHODS: Fifteen females between the 14th-32nd day of gestation were used following euthanasia. Gestational buttons were collected, fixed, processed, stained to optical microscopy or immunohistochemistry. RESULTS: Chorioallantoic placenta (CP) ranged from conical to a half-sphere, as follows: from the 14th to 17th day, the CP displays an inverted "V" shape, predominantly formed by cytotrophoblasts; from 20 to 22 days, formed almost entirely by cytotrophoblasts; at 28 days, a half sphere, with distinct lobes and interlobular area, numerous maternal gaps delimited by syncytiotrophoblasts and trophoblast giant cells; at 32 days, globose and undergoing the maturation process. Subplacenta, located between decidua and CP, initially presents septa consisting of simple columnar epithelium and after 17 days, comprising stratified epithelium. Visceral yolk sac (VYS) is attached to two CP projections between 14 and 17 days, formed by a simple cubic epithelium and inverted. Between 20 and 22 days, the epithelium displays apical villous projections with cytoplasmic vacuoles and a vascularized mesoderm. After the 24th day, the VYS near the placenta is pleated, very vascularized and villous, with decreased villi sizes further away from the placenta. CONCLUSION: The agouti CP displays similar characteristics to other hystricomorpha, including placenta lobulation, a subplacenta and an inverted vitelline placenta.


Asunto(s)
Dasyproctidae , Placentación , Embarazo , Femenino , Animales , Humanos , Placenta , Roedores , Saco Vitelino
4.
Zoomorphology ; : 1-16, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-37360222

RESUMEN

The greater rhea, Rhea americana, is a wild ratite of high scientific importance and significant and zootechnical value, especially considering the current development state of Brazilian poultry production, where research aimed at increasing the productivity of these animals has become extremely relevant. Studies concerning fetal attachments and embryonic development are paramount, as they can provide essential information concerning reproductive and nutritional animal management. However, a lack of information on greater rhea fetal morphology is noted. Therefore, the aim of the present study was to establish a standard model for fetal attachments in this species. Greater rhea eggs were incubated from 0 to 36 days, and macroscopic and microscopic embryonic attachment characterizations were performed. Histologically, all embryonic annexes exhibit germ layers, namely the ectoderm (outer layer), mesoderm (middle layer) and endoderm (inner layer). The findings indicate that greater rhea development patterns are similar to other birds.

5.
Anat Rec (Hoboken) ; 306(1): 193-212, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35808951

RESUMEN

Cardiogenesis is similar in all vertebrates, but differences in the valvuloseptal morphogenesis among non-crocodilian reptiles, birds, and mammals are noted. The origin of mesenchymal structures such as valves that regulate the passage of blood and the formation of partial septa that prevent the complete mixing of oxygen-rich and low-oxygen blood present in adult chelonians are essential in the evolutionary understanding of complete septation, endothermy and malformations, even in mammals. In this context, this study analyzed the heart morphogenesis of Podocnemis unifilis (Testudines: Podocnemididae) from the 4th to the 60th day of incubation. We identified the tubular heart stage, folding of the cardiac tube and expansion of the atrial and ventricular compartments followed by atrial septation by the septum primum, ventricle septation by partial septa, outflow tract septation and the formation of bicuspid valves with cartilage differentiation at the base. The formation of the first atrial septum with the mesenchymal cap is noted during the development of the atrial septum, joining the atrioventricular cushion on the 17th day and completely dividing the atria. Small secondary perforations appeared in the mid-cranial part, observed up to the 45th day. Partial ventricle septation into the pulmonary, venous, and arterial subcompartments takes place by trabeculae carneae thickening and grouping on the 15th day. The outflow tract forms the aorticopulmonary and interaortic septa on the 16th day and the bicuspid valves, on the 20th day. Therefore, after the first 20 days, the heart exhibits a general anatomical conformation similar to that of adult turtles.


Asunto(s)
Fibrilación Atrial , Humanos , Desarrollo Embrionario
6.
Anat Rec (Hoboken) ; 306(2): 343-353, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36054069

RESUMEN

Morphological studies of the oropharyngeal cavity of chelonians have become an interesting tool in the understanding of evolutionary processes associated with feeding habits in aquatic animals and the transition from aquatic to terrestrial forms. In this context, the aim of the present study was to describe the oropharyngeal cavity floor morphology of hawksbill sea turtle (Eretmochelys imbricata) hatchlings. Ten dead hatchlings of undefined sex were obtained from nests hatched on the coast of the state of Rio Grande do Norte, Brazil. The heads of each specimen were fixed, dissected, and analyzed at the macroscopic and microscopic levels. The oropharyngeal cavity floor of the hawksbill sea turtle hatchlings is formed by the tongue, pharynx, floor muscles, and hyolingual skeleton, delimited in the rostral and lateral directions by a keratinized beak, called the rhamphotheca, and in the caudal region at the limit between the pharynx and the esophagus. The tongue muscles and the muscles that support the floor of the oral cavity comprise the following: m. hypoglossohyoideus, m. hypoglossoglossus, m. hyoglossus, m. genioglossus, m. constrictor laryngis, m. geniohyoideus pars lateralis, and m. intermandibularis. The oropharyngeal cavity floor mucosa is formed by keratinized stratified squamous epithelium and the lamina propria is formed by loose connective tissue. The floor mucosa is devoid of taste buds. We believe that the basic oropharyngeal cavity floor characteristics in hawksbill sea turtle hatchlings may comprise indications that these animals are plesiomorphic and that semiaquatic and terrestrial turtles may have undergone adaptations to feed out of water.


Asunto(s)
Tortugas , Animales , Tortugas/anatomía & histología , Adaptación Fisiológica , Aclimatación , Membrana Mucosa , Epitelio
7.
Anim Reprod ; 19(3): e20210124, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36313597

RESUMEN

Duchenne Muscular Dystrophy (DMD) reproductive alterations and the influence of antioxidant treatments may aid in understanding morphometry testicular quantification. In this context, the aim of the present study was to characterize the intertubular compartment (ITC) morphometry of animal testes in mdx mice supplemented with ascorbic acid (AA). Sixteen mice were used, namely the C57BL/10 (non-dystrophic) and C57BL/10Mdx (dystrophic) lineages, distributed into the following groups: Control (C60), Dystrophic (D60), Control supplemented with AA (CS60), Dystrophic supplemented with AA (DS60). A total of 200 mg/kg of AA were administered to mice for 30 days. Subsequently, the testicles were collected, weighed, and fragmented. The obtained fragments were fixed in Karnovsky's solution (pH 7.2) and embedded in historesin for morphometric and transmission electron microscopy assessments. Leydig cells were hypertrophic in the D60 group, but was reverted by AA supplementation in the DS60 group. The DS60 group also exhibited increased intertubular volume compared to the CS60 group. The ultrastructural images identified multilamellar bodies in dystrophic animals (lipid storage) and telocyte cells (transport substances) in both control and dystrophic animals. Morphometric alterations were, therefore, noted in the intertubular compartment due to Duchenne muscular dystrophy (DMD), with AA administration capable of altering Leydig cells in this condition.

8.
Anim Reprod ; 19(3): e20220011, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36156880

RESUMEN

Sex steroid hormones are critical in gonadal differentiation in turtles. The gonads are not the only organs responsible for producing these hormones during this phase. Mesonephros play an important role in steroidogenesis. The present study aimed to investigate the presence of steroidogenic cells in mesonephros of Podocnemis expansa during gonadal differentiation and to evaluate their morphology and ultrastructure. Ten embryos of P. expansa were collected from 5 nests on day 36 of incubation, during spawning period on an artificial beach. Embryos were extracted from eggs by slicing the shell and euthanized. They were dissected under a stereoscopic microscope to collect the gonad-mesonephro complex, in which were fixed and subsequently processed for light microscopy, immunohistochemistry and transmission electron microscopy analysis. During histological analysis was observed mesonephros has typical morphological structure. Immunohistochemistry showed immunoreaction to aromatase in cells of intertubular space. Confirming these findings, it was possible to observe a type of intertubular cell in several regions of mesonephro, being more predominant in region close to blood vessels, distal and proximal tubules. In ultrastructural analysis these cells were characterized by having a clear, large, and rounded nucleus with evident nucleolus and cytoplasm rich in electron-dense droplets. This study demonstrated for the first time the presence of cells with morphological, immunohistochemical and ultrastructural characteristics similar to steroid-producing cells in P. expansa mesonephrons, suggesting that this organ may contribute to gonadal differentiation in this species.

9.
Anat Histol Embryol ; 51(4): 492-500, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35637627

RESUMEN

The determination of arterial vascular distribution patterns can contribute to more detailed knowledge on arterial systems. In this context, the aim of the present study was to describe the collateral aortic branches in the collared peccary, aiming to define a standard model for this species, providing information through comparative anatomy for analysis of some evolutionary aspects of the order Artiodactyla. Ten young male animals were employed. The vascular system was washed with a saline solution and then perfused with Neoprene 450 latex coloured with red or yellow pigment, followed by collateral aorta branch dissections and analyses. The contrasted digital radiography technique was applied to two animals, which were initially perfused with a barium sulphate solution (1 g/ml) and Neoprene 450 latex at a 1:3 ratio, and subsequently, the digital radiographic examination was performed. The aortic arch of the collared peccary emitted the brachiocephalic trunk and the left subclavian artery, while eight symmetric pairs of dorsal intercostal arteries originated from the thoracic aorta. The abdominal aorta, in turn, exhibited the celiac, cranial mesenteric, renal, caudal mesenteric, testicular, external iliac, internal iliac and sacral arteries as the collateral branches in all studied animals. Therefore, no relevant variations were observed regarding the arrangement of the arterial distribution of the aorta, thus suggesting a static standard model in the collared peccary.


Asunto(s)
Artiodáctilos , Látex , Animales , Aorta Abdominal , Evolución Biológica , Masculino , Neopreno
10.
Anim Reprod ; 18(2): e20200051, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34306213

RESUMEN

Glutamine is often used to treat metabolic changes associated with anorexia-cachexia syndrome in patients with malignant neoplasms. Walker 256 tumor is an excellent model for studying these changes associated with cancer in different organs, including injuries in testicular functions. However, the effects of supplementing glutamine on testicular morphometry in this model have not yet been investigated. Thus, the objective of this study was to evaluate the effect of L-glutamine supplementation on testicular morphometry in rats transplanted with Walker 256 tumor cells. Forty puberty Wistar rats were divided into four groups: control without L-glutamine (C); control supplemented with L-glutamine (CG); inoculated with Walker 256 tumor cells (WT) and inoculated with Walker 256 tumor cells and supplemented with L-glutamine (WTG). The testicles were removed, weighed, fixed in Bouin, and included in paraffin for histomorphometric analysis. Walker 256 tumor caused quantitative changes in the tubular and intertubular compartments and tunica albuginea, with reductions in the percentages of lumen and tunica albuginea, number of Sertoli cells per gram of testis; number of Leydig cells; percentage of blood vessels and connective tissue in intertubule. However, glutamine supplementation prevented part of these changes caused by the tumor, presenting mainly a protective effect on the tunica albuginea and percentage of blood and lymph vessels in the intertubule. These results indicate the potential of L-glutamine was able to recover for testicular dysfunction associated with cancer.

11.
J Morphol ; 280(8): 1232-1245, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31233245

RESUMEN

The study investigated the gross and microscopic anatomy of the genital organs of 20 agoutis at different stages of the estrous cycle and four in the final trimester of pregnancy. Specimens were euthanized and their reproductive organs were fixed in a 4% paraformaldehyde or 2.5% glutaraldehyde solution and submitted to routine histological techniques for light and scanning electron microscopy. In the ovary, during the proestrus phase, we observed developing follicles and corpus luteum (CL) in regression; during estrus, there were Graafian follicles; during metestrus, there was a hemorrhagic corpus, whereas in diestrus, there was a mature CL. The uterus was partially double because the cervix was cranially septate but caudally, the septum disappeared, forming a single ostium that opened into the vagina. Changes occurred along the estrous cycle in the uterine and vaginal epithelia, that is, an increase in the uterine epithelium height accompanied by an increase of thickness of the vaginal epithelium during the follicular phase and a decrease of thickness of both epithelia during the luteal phase. The endometrial lining was composed of a simple cuboidal epithelium to simple columnar epithelium with basal nuclei. The vaginal mucosa consisted of epithelium that varied from nonkeratinized stratified squamous (luteal phase) to keratinized stratified squamous (follicular phase). The clitoris was external to the vagina. It presented two protruding lateral keratinized spicules and a centralized urethra, with no common parts between the urinary and genital tracts. Anatomical and histological changes were observed mainly in the cervix, vagina and spicules of the clitoris during the EC.


Asunto(s)
Dasyproctidae/anatomía & histología , Dasyproctidae/fisiología , Ciclo Estral/fisiología , Genitales Femeninos/anatomía & histología , Animales , Epitelio/ultraestructura , Femenino , Genitales Femeninos/citología , Genitales Femeninos/ultraestructura , Embarazo , Frotis Vaginal
12.
Theriogenology ; 121: 78-81, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30144734

RESUMEN

The objective of this study was to evaluate effects of eCG on vascularization and development of feline ovarian tissue xenografted to immunosuppressed mice. Feline ovarian fragments (∼1 mm3) were transplanted under the renal capsule of 20 adult, ovariectomized, C57BL/6 SCID female mice. At 45 d after transplantation, 10 mice (controls) were euthanized and the remainder given 10 IU of eCG (and sacrificed 48 h later). Transplants were recovered immediately after death, fixed, sectioned, and stained with periodic acid-Schiff (PAS). Fragment volume (Cavallieri principle) and vascularization were assessed. Mean xenotransplant volume for control and treatment groups was 0.17 ±â€¯0.03 and 0.37 ±â€¯0.13 mm3, respectively (P = 0.0952); vascular volume density, 30.3 ±â€¯11.3 and 49.1 ±â€¯8.9% (P = 0.0281); surface density, 4.1 ±â€¯2.4 and 6.2 ±â€¯1.7 µm-1 (P = 0.2222); and vessel total surface, 0.63 ±â€¯0.24 µm2 and 2.28 ±â€¯1.05 µm2 (P = 0.0079). In conclusion, eCG significantly increased vascular volume density of xenotransplanted ovarian tissue and improved its development.


Asunto(s)
Gatos , Gonadotropina Coriónica/uso terapéutico , Xenoinjertos/irrigación sanguínea , Neovascularización Fisiológica/efectos de los fármacos , Ovario/trasplante , Trasplante de Tejidos/veterinaria , Animales , Femenino , Gonadotropinas Equinas/farmacología , Ratones Endogámicos C57BL , Ratones SCID , Ovario/irrigación sanguínea , Trasplante de Tejidos/métodos , Trasplante Heterólogo
13.
Anim Reprod Sci ; 182: 35-47, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28502649

RESUMEN

Fourteen pregnant agouti (Dasyprocta leporina Linnaeus, 1758) females at gestational ages of 30-100days and two at gestational ages of 55-100days, were studied, including 24 embryos/fetuses and two neonates (single offspring from two females). Females were euthanized and embryos/fetuses were examined, measured, and photographed. Embryos at 30days post-copulation were "C-shaped," with paddle-shaped limb buds and 10.75±0.11mm crown-rump length (CRL). In embryos at 35days post-copulation, paddle-shaped forelimbs, fin-shaped pelvic limbs, and a liver bud were evident, with 15.6±0.16mm CRL; at 45days, mouth and nostrils were evident, lower incisors were emerging, and tactile hairs could be seen near the nostrils, with 40.8±0.4mm CRL; at 55days, cranial sutures had fused, digits were totally separated and claws formation was beginning, with 58.8±0.1mm CRL; at 65days, the genital bud had differentiated, with 83±0.08mm CRL; at 85days, the body was covered with short hair, with 127.7±0.6mm CRL; and at 100days, the mature fetus had fully formed teeth and claws and an open external acoustic meatus, with 164.3±10.4mm CRL. Neonates had bristly hair and open eyes, with 179.1±0.5mm CRL. In conclusion, characteristics of the embryo/fetus during pregnancy can be used to estimate gestational age, and can be used as parameters during ultrasound examinations to help identify developmental pathologies and to test effects of nutrition, drugs, and pollution on pregnancy.


Asunto(s)
Dasyproctidae/embriología , Desarrollo Embrionario/fisiología , Preñez , Animales , Animales Recién Nacidos , Dasyproctidae/anatomía & histología , Dasyproctidae/crecimiento & desarrollo , Femenino , Embarazo
14.
Toxicology ; 262(2): 138-45, 2009 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-19520141

RESUMEN

Titanium (Ti) is currently the most widely used material for the manufacture of orthopedic and dental implants. Changes in the surface of commercial pure Ti (cp Ti) can determine the functional response of cells, and is therefore a critical factor for the success of the implant. However, the genotoxicity of titanium surfaces has been poorly studied. Thus, the purpose of this study was to evaluate the genotoxic potential of a new titanium surface developed by plasma treatment using argon-ion bombardment and compare it with an untreated titanium surface. Accordingly, comet assay, analysis of chromosomal aberrations (CAs), and Cytokinesis Block Micronucleus (CBMN) assay were carried out, using CHO-K1 (Chinese hamster ovary) cells grown on both titanium surfaces. Our results show that the untreated titanium surface caused a significant increase in % tail moment, in the number of cells with CAs, tetraploidy, micronucleus frequency, and other nuclear alterations when compared with the negative control and with the plasma-treated titanium surface. This difference may be attributed to increased surface roughness and changes in titanium oxide layer thickness.


Asunto(s)
Aberraciones Cromosómicas/inducido químicamente , Micronúcleos con Defecto Cromosómico/inducido químicamente , Mutágenos/toxicidad , Titanio/toxicidad , Animales , Argón , Células CHO , Núcleo Celular/efectos de los fármacos , Núcleo Celular/patología , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/efectos de la radiación , Ensayo Cometa , Cricetinae , Cricetulus , Iones , Pruebas de Micronúcleos , Mutágenos/efectos de la radiación , Propiedades de Superficie/efectos de la radiación , Titanio/efectos de la radiación
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